CN110710297A

CN110710297A - Cellular reporting techniques for synchronized state changes

Info

Publication number: CN110710297A
Application number: CN201880004307.5A
Authority: CN
Inventors: 许芳丽; 张大伟; 胡海静; 陈玉芹
Original assignee: Apple Inc
Current assignee: Apple Inc
Priority date: 2018-05-10
Filing date: 2018-05-10
Publication date: 2020-01-17
Anticipated expiration: 2038-05-10
Also published as: US20220256490A1; CN110710297B; EP4138493A1; KR20200135879A; KR102267978B1; EP3777386A4; US11330538B2; US11895602B2; US20210329578A1; EP3777386B1; WO2019213892A1; EP3777386A1

Abstract

Techniques are disclosed that relate to reporting Channel State Information (CSI) when synchronization state changes. In some embodiments, a UE starts a Timing Alignment Timer (TAT) in response to a Time Alignment Command (TAC) from a cellular network for one or more serving cells. In some embodiments, the UE stores a configuration of semi-persistent (SP) Channel State Information (CSI) reports for the apparatus on a Physical Uplink Shared Channel (PUSCH). In some embodiments, the UE activates the SP-CSI report based on Downlink Control Information (DCI) from the network. In some embodiments, the UE transmits one or more SP-CSI reports according to the configuration. In some embodiments, in response to expiration of the TAT, the UE stops using the PUSCH and all active storage configurations for SP-CSI reporting for the one or more serving cells. In some embodiments, this may avoid collision with PUSCH transmissions from other UEs, e.g., when the UE returns to a synchronized state.

Description

Cellular reporting techniques for synchronized state changes

Technical Field

The present application relates to wireless communications, and more particularly to cellular reporting of, for example, channel state information.

Background

The use of wireless communication systems is growing rapidly. In addition, there are a number of different wireless communication technologies and standards. Some examples of wireless communication technologies include New Radio (NR), GSM, UMTS (e.g., associated with WCDMA or TD-SCDMA air interfaces), LTE-advanced (LTE-A), HSPA, 3GPP2CDMA2000 (e.g., 1xRTT, 1xEV-DO, HRPD, eHRPD), IEEE 802.11(WLAN or Wi-Fi), IEEE 802.16(WiMAX), Bluetooth, and so forth.

In general, wireless communication should efficiently allocate time and frequency resources (e.g., of a shared channel) while avoiding collisions between UEs using the resources.

Drawings

A better understanding of the present subject matter can be obtained when the following detailed description of the embodiments is considered in conjunction with the following drawings, in which:

fig. 1 illustrates an exemplary (and simplified) wireless communication system in accordance with some embodiments.

Fig. 2 illustrates a Base Station (BS) in communication with a User Equipment (UE) device, in accordance with some embodiments.

Fig. 3 illustrates an exemplary block diagram of a UE in accordance with some embodiments.

Fig. 4 illustrates an exemplary block diagram of a BS according to some embodiments.

Fig. 5 is a diagram illustrating an example CSI reporting mode, according to some embodiments.

Fig. 6 is a communication diagram illustrating an exemplary collision scenario for SP-CSI reporting on PUSCH.

Fig. 7 is a flow diagram illustrating an example technique for disabling configured SP-CSI reporting upon entering an out-of-sync state, according to some embodiments.

Fig. 8 is a flow diagram illustrating another example method for disabling configured SP-CSI reporting upon entering an out-of-sync state, according to some embodiments.

This specification includes references to various embodiments to indicate that the disclosure is not intended to reference a particular implementation, but rather a list of embodiments that fall within the spirit of the disclosure, including the appended claims. The particular features, structures, or characteristics may be combined in any suitable manner consistent with the present disclosure.

Within this disclosure, different entities (which may be referred to variously as "units," "circuits," other components, etc.) may be described or claimed as "configured to" perform one or more tasks or operations. This expression-an [ entity ] configured to [ perform one or more tasks ] -is used herein to refer to a structure (i.e., a physical thing, such as an electronic circuit). More specifically, this expression is used to indicate that the structure is arranged to perform one or more tasks during operation. A structure may be said to be "configured to" perform a task even though the structure is not currently being operated on. "UE wireless processor configured to communicate with a base station" is intended to cover, for example, circuitry that performs this function during operation, even though the circuitry in question is not currently being used (e.g., power is not connected to the circuitry). Thus, an entity described or stated as "configured to" perform a task refers to physical things such as devices, circuits, memories storing executable program instructions, etc. that are used to perform the task. This phrase is not used herein to refer to intangible matter.

The term "configured to" is not intended to mean "configurable to". For example, an unprogrammed FPGA would not be considered "configured to" perform a particular function, although it may be "configurable" to perform that function. After appropriate programming, the FPGA can then be configured to perform this function.

The expression "configured to" perform one or more tasks in the appended claims is expressly intended to exclude 35u.s.c. § 112(f) from such claim elements. Thus, no claim in the filed application is intended to be construed as having a device-plus-function element. If applicants intend to refer to segment 112(f) during the prosecution of the application, then they will use the structure of "means for" [ performing a function ] "to recite a claim element.

As used herein, the term "based on" is used to describe one or more factors that affect the determination. This term does not exclude that there may be additional factors that may influence the determination. That is, the determination may be based on the specified factors alone or on the specified factors and other unspecified factors. Consider the phrase "determine a based on B. This phrase specifies that B is a factor used to determine a or that B affects a determination. This phrase does not exclude that the determination of a may also be based on some other factor such as C. This phrase is also intended to cover embodiments in which a is determined based on B only. As used herein, the phrase "based on" is synonymous with the phrase "based, at least in part, on".

Detailed Description

Acronyms

The following acronyms may be used in this disclosure.

3 GPP: third generation partnership project

3GPP 2: third generation partnership project 2

APN: access point name

BLER: block error rate (same as packet error rate)

BER: error rate

CRC: cyclic redundancy check

DL: downlink link

GBR: guaranteed bit rate

GSM: global mobile communication system

IMS: IP multimedia subsystem

IP: internet protocol

LTE: long term evolution

MME: mobility management entity

MO: source of message

MT: message termination

NAS: non-access stratum

PCC: policy and charging control

A PCEF: policy and charging enforcement function

PCRF: policy and charging rules function

PCSCF: proxy call session control function

PGW: packet gateway

PER: packet error rate

QCI: quality of service class indexing

QoS: quality of service

RAT (RAT): radio access technology

RRC: radio resource control

SGW: service gateway

SINR: signal to interference plus noise ratio

SIR: signal to interference ratio

SNR: signal to noise ratio

Tx: transmission of

UE: user equipment

UL: uplink link

UMTS: universal mobile telecommunications system

VoLTE: long term evolution voice bearer

Term(s) for

The following is a glossary of terms used in this disclosure:

memory medium-any of various types of non-transitory memory devices or storage devices. The term "storage medium" is intended to include mounting media such as CD-ROM, floppy disk, or tape devices; computer system memory or random access memory such as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM, etc.; non-volatile memory such as flash memory, magnetic media, e.g., a hard disk drive or optical storage; registers or other similar types of memory elements, and the like. The memory medium may also include other types of non-transitory memory or combinations thereof. Further, the memory medium may be located in a first computer system executing the program, or may be located in a different second computer system connected to the first computer system through a network such as the internet. In the latter case, the second computer system may provide program instructions to the first computer for execution. Term(s) forA "memory medium" may include two or more memory media that may reside at different locations in different computer systems connected, for example, by a network. The memory medium may store program instructions (e.g., embodied as a computer program) that are executable by one or more processors.

Carrier mediumMemory media as described above, as well as physical transmission media such as buses, networks, and/or other physical transmission media that convey signals such as electrical, electromagnetic, or digital signals.

Computer systemAny of various types of computing systems or processing systems, including Personal Computer Systems (PCs), mainframe computer systems, workstations, network appliances, internet appliances, Personal Digital Assistants (PDAs), television systems, grid computing systems, or other devices or combinations of devices. In general, the term "computer system" may be broadly defined to encompass any device (or combination of devices) having at least one processor that executes instructions from a memory medium.

User Equipment (UE) (or "UE device")Any of various types of computer system devices that are mobile or portable and perform wireless communications. Examples of UE devices include mobile phones or smart phones (e.g., iphones)^TMBased on Android^TMTelephone), portable gaming devices (e.g., Nintendo DS)^TM、PlayStation Portable^TM、Gameboy Advance^TM、iPhone^TM) A laptop computer, a wearable device (e.g., a smart watch, smart glasses), a PDA, a portable internet appliance, a music player, a data storage device, or other handheld device, etc. In general, the term "UE" or "UE device" may be broadly defined to encompass any electronic device, computing device, and/or telecommunications device (or combination of devices) that is easily transported by a user and capable of wireless communication.

Base stationThe term "base station" has its full scope in its ordinary meaning and includes at least a base station installed at a fixed location and intended to be part of a wireless cellular telephone system or a cellular radio systemA communicating wireless communication station.

Processing element-refers to various elements or combinations of elements capable of performing functions in a device, such as a user equipment or a cellular network device. The processing elements may include, for example: a processor and associated memory, portions or circuitry of individual processor cores, an entire processor core, a processor array, circuitry such as an ASIC (application specific integrated circuit), programmable hardware elements such as Field Programmable Gate Arrays (FPGAs), and any of a variety of combinations thereof.

Channel with a plurality of channels-a medium for transferring information from a sender (transmitter) to a receiver. It should be noted that the term "channel" as used herein may be considered to be used in a manner that conforms to a standard for the type of device to which the term is being referred, since the characteristics of the term "channel" may differ from one wireless protocol to another. In some standards, the channel width may be variable (e.g., depending on device capabilities, band conditions, etc.). For example, LTE may support a scalable channel bandwidth of 1.4MHz to 20 MHz. In contrast, a WLAN channel may be 22MHz wide, while a bluetooth channel may be 1MHz wide. Other protocols and standards may include different definitions for channels. Further, some standards may define and use multiple types of channels, e.g., different channels for uplink or downlink and/or different channels for different purposes such as data, control information, and so on.

BeltThe term "band" has its full scope in its ordinary meaning and includes at least a section of spectrum (e.g., the radio frequency spectrum) in which channels are used or set aside for the same purpose.

AutomaticRefer to actions or operations performed by a computer system (e.g., software executed by a computer system) or device (e.g., a circuit, a programmable hardware element, an ASIC, etc.) without user input directly specifying or performing the action or operation. Thus, the term "automatically" is in contrast to an operation that is manually performed or specified by a user, wherein the user provides input to directly perform the operation. An automated process may be initiated by input provided by a user, with subsequent "automatically" performed actions not specified by the userThat is, not "manually" performed, where the user specifies each action to perform. For example, a user filling out an electronic form by selecting each field and providing input specifying information (e.g., by typing information, selecting a check box, radio selection, etc.) is manually filling out the form, even though the computer system must update the form in response to user action. The form may be automatically filled in by a computer system, wherein the computer system (e.g., software executing on the computer system) analyzes the fields of the form and fills in the form without any user entering answers specifying the fields. As indicated above, the user may invoke automatic filling of the form, but not participate in the actual filling of the form (e.g., the user does not manually specify answers for the fields but rather they are automatically completed). This specification provides various examples of operations that are automatically performed in response to actions that have been taken by a user.

FIGS. 1 and 2—Communication system

Fig. 1 illustrates an exemplary (and simplified) wireless communication system in accordance with some embodiments. It is noted that the system of fig. 1 is only one example of possible systems, and embodiments may be implemented in any of a variety of systems, as desired.

As shown, the exemplary wireless communication system includes a base station 102A that communicates with one or more user devices 106A, 106B, etc. to a user device 106N over a transmission medium. Each of the user equipments may be referred to herein as a "user equipment" (UE). Thus, the user equipment 106 is referred to as a UE or UE device.

The base station 102A may be a Base Transceiver Station (BTS) or a cell site and may include hardware that enables wireless communication with the UEs 106A-106N. The base station 102A may also be equipped to communicate with a network 100 (e.g., a core network of a cellular service provider, a telecommunications network such as a Public Switched Telephone Network (PSTN) and/or the internet, among various possibilities). Thus, base station 102A may facilitate communication between User Equipments (UEs) and/or between UEs and network 100.

The communication area (or coverage area) of a base station may be referred to as a "cell". The base station 102A and the UE106 may be configured to communicate over a transmission medium using any of a variety of Radio Access Technologies (RATs), also referred to as wireless communication technologies or telecommunication standards, such as GSM, UMTS (WCDMA, TD-SCDMA), LTE-advanced (LTE-a), HSPA, 3GPP2CDMA2000 (e.g., 1xRTT, 1xEV-DO, HRPD, eHRPD), Wi-Fi, WiMAX, and so forth.

Base station 102A and other similar base stations (such as base stations 102b.. 102N) operating according to the same or different cellular communication standards may thus be provided as a network of cells that can provide continuous or nearly continuous overlapping service to UEs 106A-160N and similar devices over a wide geographic area via one or more cellular communication standards.

Thus, while base station 102A may serve as a "serving cell" for UEs 106A-160N as shown in fig. 1, each UE106 may also be within communication range of and capable of receiving signals from one or more other cells (which may be provided by base stations 102B-N and/or any other base stations), which may be referred to as "neighbor cells. Such cells may also be capable of facilitating communication between user devices and/or between user devices and network 100 according to the same wireless communication technology as base station 102A and/or any of a variety of other possible wireless communication technologies. Such cells may include "macro" cells, "micro" cells, "pico" cells, and/or cells providing any of a variety of other granularities of service area size. For example, the base stations 102A-B shown in fig. 1 may be macro cells, while the base station 102N may be a micro cell. Other configurations are also possible.

Note that the UE106 may be capable of communicating using multiple wireless communication standards. For example, in addition to at least one cellular communication protocol (e.g., GSM, UMTS (WCDMA, TD-SCDMA), LTE-A, HSPA, 3GPP2CDMA2000 (e.g., 1xRTT, 1xEV-DO, HRPD, eHRPD), etc.), UE106 may be configured to communicate using wireless networking (e.g., Wi-Fi) and/or peer-to-peer wireless communication protocols (e.g., BT, Wi-Fi pairs, etc.). If desired, the UE106 may also or alternatively be configured to communicate using one or more global navigation satellite systems (GNSS, such as GPS or GLONASS), one or more mobile television broadcast standards (e.g., ATSC-M/H or DVB-H), and/or any other wireless communication protocol. Other combinations of wireless communication standards, including more than two wireless communication standards, are also possible.

Fig. 2 illustrates a user equipment 106 (e.g., one of the devices 106A-106N) in communication with a base station 102 (e.g., one of the base stations 102A-102N), in accordance with some embodiments. The UE106 may be a device with cellular communication capabilities, such as a mobile phone, a handheld device, a wearable device, a computer or a tablet, or virtually any type of wireless device.

The UE106 may include a processor configured to execute program instructions stored in a memory. The UE106 may perform any of the method embodiments described herein by executing such stored instructions. Alternatively or additionally, the UE106 may include programmable hardware elements, such as an FPGA (field programmable gate array) configured to perform any of the method embodiments described herein or any portion of any of the method embodiments described herein. Alternatively or additionally, the UE106 may include one or more integrated circuits configured to perform any of the method embodiments described herein.

The UE106 may include one or more antennas for communicating using one or more wireless communication protocols or technologies. In some embodiments, the UE106 is configured to communicate using CDMA2000(1xRTT/1xEV-DO/HRPD/eHRPD) or LTE using a single shared radio and/or either GSM or LTE using a single shared radio. The shared radio may be coupled to a single antenna or may be coupled to multiple antennas (e.g., for MIMO) for performing wireless communications. In general, the radio components may include any combination of baseband processors, analog RF signal processing circuits (e.g., including filters, mixers, oscillators, amplifiers, etc.), or digital processing circuits (e.g., for digital modulation and other digital processing). Similarly, the radio may implement one or more receive chains and transmit chains using the aforementioned hardware. For example, the UE106 may share one or more portions of a receive chain and/or a transmit chain among multiple wireless communication technologies, such as those discussed above.

In some embodiments, the UE106 may include separate (and possibly multiple) transmit chains and/or receive chains (e.g., including separate RF and/or digital radios) for each wireless communication protocol with which it is configured to communicate. As another possibility, the UE106 may include one or more radios shared between multiple wireless communication protocols, as well as one or more radios used exclusively by a single wireless communication protocol. For example, the UE106 may include a shared radio for communicating using either LTE or 1xRTT (or LTE or GSM), and a separate radio for communicating using each of Wi-Fi and bluetooth. Other configurations are also possible.

FIG. 3—Exemplary Block diagrams for a UE

Fig. 3 illustrates an exemplary block diagram of a UE106 according to some embodiments. As shown, the UE106 may include a System On Chip (SOC)300, which SOC300 may include processing elements for various purposes. For example, as shown, SOC300 may include one or more processors 302 that may execute program instructions for UE106, and display circuitry 304 that may perform graphics processing and provide display signals to display 360. The one or more processors 302 may also be coupled to a Memory Management Unit (MMU)340 (the Memory Management Unit (MMU)340 may be configured to receive addresses from the one or more processors 302 and translate those addresses to locations in memory (e.g., memory 306, Read Only Memory (ROM)350, NAND flash memory 310) and/or to other circuits or devices (such as display circuitry 304, wireless communication circuitry 330, connector I/F320, and/or display 360). MMU 340 may be configured to perform memory protections and page table translations or settings. In some embodiments, MMU 340 may be included as part of processor 302.

As shown, the SOC300 may be coupled to various other circuits of the UE 106. For example, the UE106 may include various types of memory (e.g., including NAND flash memory 310), a connector interface 320 (e.g., for coupling to a computer system, docking station, charging station, etc.), a display 360, and wireless communication circuitry 330 (e.g., for LTE, Wi-Fi, GPS, etc.).

The UE device 106 may include at least one antenna for performing wireless communication with base stations and/or other devices (and in various possibilities, there may be multiple antennas, e.g., for MIMO and/or for implementing different wireless communication technologies). For example, the UE device 106 may perform wireless communication using the antenna 335. As mentioned above, in some embodiments, the UE106 may be configured to wirelessly communicate using multiple wireless communication standards.

As described further herein subsequently, the UE106 may include hardware and software components for implementing the features and methods described herein. The processor 302 of the UE device 106 may be configured to implement some or all of the methods described herein, for example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). In other embodiments, the processor 302 may be configured as a programmable hardware element such as an FPGA (field programmable gate array), or as an ASIC (application specific integrated circuit). Alternatively (or in addition), the processor 302 of the UE device 106, in conjunction with one or more of the

other components

300, 304, 306, 310, 320, 330, 335, 340, 350, 360, may be configured to implement some or all of the features described herein.

FIG. 4—Exemplary Block diagrams of base stations

Fig. 4 illustrates an example block diagram of a base station 102 in accordance with some embodiments. It is noted that the base station of fig. 4 is only one example of possible base stations. As shown, base station 102 may include one or more processors 404 that may execute program instructions for base station 102. The one or more processors 404 may also be coupled to a Memory Management Unit (MMU)440 (which may be configured to receive addresses from the one or more processors 404 and translate the addresses to locations in memory (e.g., memory 460 and Read Only Memory (ROM) 450)) or other circuitry or device.

The base station 102 may include at least one network port 470. The network port 470 may be configured to couple to a telephone network and provide a plurality of devices, such as the UE device 106, with access to the telephone network as described above in fig. 1 and 2.

The network port 470 (or additional network ports) may also or alternatively be configured to couple to a cellular network, such as a core network of a cellular service provider. The core network may provide mobility-related services and/or other services to multiple devices, such as UE device 106. In some cases, the network port 470 may be coupled to a telephone network via a core network, and/or the core network may provide the telephone network (e.g., in other UE devices served by a cellular service provider).

The base station 102 may include at least one antenna 434 and possibly multiple antennas. The antenna 434 may be configured to operate as a wireless transceiver and may also be configured to communicate with the UE device 106 via the radio 430. Antenna 434 communicates with radio 430 via communication link 432. Communication chain 432 may be a receive chain, a transmit chain, or both. Radio 430 may be configured to communicate via various wireless telecommunication standards including, but not limited to, LTE-a, UMTS, CDMA2000, Wi-Fi, and the like.

Base station 102 may be configured to communicate wirelessly using a plurality of wireless communication standards. In some cases, base station 102 may include multiple radios that may enable base station 102 to communicate in accordance with multiple wireless communication technologies. For example, as one possibility, base station 102 may include an LTE radio to perform communications according to LTE and a Wi-Fi radio to perform communications according to Wi-Fi. In such cases, base station 102 may be capable of operating as both an LTE base station and a Wi-Fi access point. As another possibility, base station 102 may include a multi-mode radio capable of performing communications in accordance with any of a number of wireless communication technologies (e.g., LTE and Wi-Fi).

Base station 102 may include hardware and software components for implementing or supporting the implementations of features described herein. The processor 404 of the base station 102 may be configured to implement a portion or all of the methods described herein, for example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively, the processor 404 may be configured as a programmable hardware element such as an FPGA (field programmable gate array) or as an ASIC (application specific integrated circuit) or a combination thereof. Alternatively (or in addition), processor 404 of base station 102, in conjunction with one or more of the

other components

430, 432, 434, 440, 450, 460, and/or 470, may be configured to implement or support the implementation of some or all of the features described herein.

Overview of synchronization status and reporting modes

In some embodiments, the UE has at least two synchronization states for uplink transmissions: synchronous and asynchronous. These embodiments may include cellular networks implementing the LTE or 5G standards, among others. In the synchronized state, the UE synchronizes with the cellular network for uplink transmissions (e.g., using a Physical Uplink Control Channel (PUCCH), a Physical Uplink Shared Channel (PUSCH), and/or a Sounding Reference Signal (SRS)). In the out-of-sync state, the UE should not perform any uplink transmission except using a preamble (e.g., using the preamble as part of a Random Access Channel (RACH) procedure to acquire uplink synchronization).

In some embodiments, a Timing Alignment Timer (TAT) controls the UE synchronization state. The TAT may be started based on receiving a timing advance command (TA) from the network, e.g., via a timing command (TAC) Media Access Control (MAC) Control Element (CE). In some embodiments, the duration of the TAT is configured by the cellular network and the TAT is reset when the UE receives the TAC.

In some embodiments, when the TAT expires, the UE is configured to enter an out-of-sync state and release all dedicated physical uplink resources (e.g., PUCCH and SRS). It should be noted that in some embodiments, the UE may not release the shared uplink resource (such as PUSCH) when entering the out-of-sync state.

In some embodiments, the UE is configured to re-enter the in-synchronization state by performing a Random Access Channel (RACH) procedure to acquire initial uplink time alignment. In some embodiments, the UE is further configured to re-enter the synchronization state upon receiving the TAC MAC CE from the network. As discussed in further detail below, UEs that are not synchronized and then re-enter the synchronized state may be configured and activated to report on the shared channel. This may result in collisions with other uplink transmissions if the network has allocated resources to other UEs during the out-of-sync interval.

Fig. 5 is a diagram illustrating exemplary types of Channel State Information (CSI) reports, according to some embodiments. In the illustrated embodiment, the types include aperiodic, periodic, and semi-persistent (SP). As shown, the SP-CSI may be configured as PUCCH and/or PUSCH. Note that aperiodic CSI and periodic CSI may be used in both LTE and New Radio (NR), while SP-CSI may be part of the NR.

In the illustrated embodiment, the aperiodic CSI uses PUSCH and is triggered by Downlink Control Information (DCI). Its resources are not released at TAT expiration (e.g., because aperiodic CSI is a one-time report, its resources are dynamically scheduled and not maintained at the UE end after transmission is complete). In general, PUSCH may be used to convey RRC signaling messages/application data and Uplink Control Information (UCI). Thus, the PUSCH may include user information, data, and control signaling data from multiple UEs. Conventionally, PUSCH resource allocation is dynamic and scheduled by the network such that the UE does not reserve resources after using its dynamic allocation. The DCI may include a control signaling message transmitted on a Physical Downlink Control Channel (PDCCH) and may include, for example, an uplink transmission grant for a PUSCH.

In the illustrated embodiment, the periodic CSI uses PUCCH and is based on RRC configuration (no dynamic triggering/activation). As shown, resources for periodic CSI reporting are released upon TAT expiration. In general, the PUCCH may be used to transmit Uplink Control Information (UCI) and/or transmit various combinations of Scheduling Reports (SR), hybrid automatic repeat request (HARQ) acknowledgements, and Channel State Information (CSI) reports. In some embodiments, the PUCCH may be used when the UE has no application data or RRC signaling. In some embodiments, PUCCH resources for CSI reporting are dedicated to UEs using the channel.

For some wireless communication implementations, a given cell may have multiple transmission points, and UEs may communicate using beams of different points and/or given transmission points, e.g., as they move through the cell. In this case, the network may activate or deactivate semi-persistent (SP) CSI reporting by the UE based on the corresponding network resources being utilized.

In the illustrated embodiment, SP-CSI on PUCCH is triggered by MAC CE for CSI activation or deactivation. As shown, resources of the SP-CSI on the PUCCH are released at TAT expiration.

In the illustrated embodiment, the SP-CSI on PUSCH is triggered by DCI and no resources are released upon TAT expiration. In general, resources may not be released because of the shared nature of PUSCH and the traditional dynamic nature of allocations on PUSCH (meaning that resources do not traditionally need to be released to increase available resources for other UEs, unlike dedicated channel portions such as PUCCH). However, unlike aperiodic CSI reporting, which is a one-time report, SP-CSI reporting on PUSCH may continue until deactivated in a semi-persistent manner (e.g., in response to a change in the location or radio conditions of the UE). Thus, using SP-CSI of a shared channel such as PUSCH may result in collisions between resources for different UEs, as discussed in detail below.

In other words, in typical existing networks, CSI reporting using only shared channels is aperiodic reporting. Potential collision problems may arise in newer networks that share channels for semi-persistent CSI reporting.

Exemplary conflict situations and techniques for avoiding conflicts

When PUSCH is used for SP-CSI, there may be a risk of collision when the UE changes the synchronization state. Fig. 6 is a communication diagram illustrating a potential deactivation scenario according to some embodiments.

As shown, an element of the cellular network (e.g., a base station) activates SP-CSI reporting on PUSCH for the UE106, e.g., using MAC CE. In some embodiments, the resources for CSI Reference Signals (RSs) are configured using RRC configuration (e.g., prior to activation), and the SP-CSI reporting periodicity pattern may be configured (e.g., by specifying periodicity and offset). Based on the activated configuration, the UE106 sends SP-CSI reports on PUSCH to the network 100 (three reports in this example). As discussed above, the UE106 may store information indicating the configuration of SP-CSI reporting on PUSCH and SP-CSI reporting is activated. Based on the TAT expiration, the UE106 then becomes out of synchronization. Subsequently, the UE106 performs the RACH procedure and re-enters the synchronization state. Based on the previously stored SP-CSI configuration, the UE106 then sends an SP-CSI report on the PUSCH.

However, although the UEs 106 are not synchronized, the network may have allocated PUSCH resources for SP-CSI reporting to other UEs (e.g., to provide efficient utilization of network resources). Thus, the transmission of the UE106 may potentially collide with uplink transmissions from other UEs, which may in turn prevent the network from correctly decoding the uplink data. It should be noted that the network may use DCI (e.g., scrambled with SP-CSI-RNTI) to deactivate activated SP-CSI reporting. However, once the UE has become out of sync, it cannot transmit an acknowledgement of the DCI in some embodiments. Thus, in these embodiments, the network cannot ensure the success of the transmission of the disable command.

Thus, in some embodiments, to respond out of sync (e.g., to respond to TAT expiration), the UE106 is configured to set the state of all configured PUSCH SP-CSI reports on the corresponding serving cell to inactive. The UE may be configured to perform this deactivation without instructions from the network. In other embodiments, the UE may be configured to delete the configuration for PUSCH SP-CSI instead of deactivating them. Thus, in some embodiments, upon re-entering the synchronization state of one or more serving cells, the UE106 will not have any active SP-CSI reports configured for PUSCH, which may avoid collision of PUSCH resources allocated to other UEs. Based on these techniques, the network may safely reallocate PUSCH resources of an out-of-sync UE to other UEs.

Fig. 7 is a flow diagram illustrating such a technique according to some embodiments. At 710, in the illustrated embodiment, the TAT for the UE106 expires for one or more serving cells. In response, at 720 in the illustrated embodiment, the UE106 sets the status of all PUSCH SP-CSI reports configured on the corresponding serving cell to inactive. In some embodiments, the network may reactivate one or more SP-CSI reports deactivated by the UE after the UE returns to the synchronized state. The stored activity configuration to deactivate SP-CSI reporting using PUSCH may include one or more of: releasing PUSCH resources allocated for SP-CSI reporting via DCI, suspending PUSCH resources allocated for SP-CSI reporting via DCI, deactivating SP-CSI-RS resources, and/or stopping measurements for corresponding CSI-RS resources.

Exemplary method

Fig. 8 is a flow diagram illustrating an example method for deactivating configured SP-CSI reporting on PUSCH, in accordance with some embodiments. The method shown in fig. 8 may be used, among other things, in conjunction with any of the computer circuits, systems, devices, elements, or components disclosed herein. In various embodiments, some of the method elements shown may be performed concurrently in a different order than shown, or may be omitted. Additional method elements may also be performed as desired.

At 810, in the illustrated embodiment, the mobile device starts a Timing Alignment Timer (TAT) in response to a Time Alignment Command (TAC) from the cellular network. This is one example of the amount of time that the mobile device tracks has elapsed since the last time alignment with the cellular network for one or more serving cells. In some embodiments, the TAC may be included in the TAC MAC CE.

At 820, in the illustrated embodiment, the mobile device stores a configuration for semi-persistent (SP) Channel State Information (CSI) reporting for a Physical Uplink Shared Channel (PUSCH) based on Radio Resource Configuration (RRC) information from the cellular network. This is one example of a mobile device that stores a configuration of a semi-persistent report in response to configuration information from a cellular network. The configuration may indicate one or more of the following: the frequency of transmission of the report, the resources of transmission of the report, the reference signals to be used for the measurements, the content of the report, etc.

At 830, in the illustrated embodiment, the mobile device activates configuration of the SP-CSI report based on Downlink Control Information (DCI) from the cellular network.

At 840, in the illustrated embodiment, the mobile device transmits one or more SP-CSI reports according to the active stored configuration. This is one example of a mobile device sending one or more reports using a shared uplink channel, depending on the configuration.

At 850, in the illustrated embodiment, in response to expiration of the TAT, the mobile device deactivates using the PUSCH and all active stored configurations for SP-CSI reporting for one or more serving cells. This is one example of the mobile device deactivating all stored configurations using a shared uplink channel and corresponding to reporting of one or more serving cells in response to detecting that a predetermined time interval has elapsed since a most recent time alignment with the cellular network.

It should be noted that in some cases, disabling all stored configurations for SP-CSI reporting may involve disabling only a single stored configuration. In some embodiments, the UE may delete the stored configuration in addition to or instead of deactivating the stored configuration.

In some embodiments, the mobile device enters the out-of-sync state in response to expiration of the TAT. In some embodiments, the deactivation of the stored configuration prevents a collision between the stored configuration and an SP-CSI report on a PUSCH configured by the cellular network for another UE. In some embodiments, the mobile device re-enters the synchronization state based on performing a Random Access Channel (RACH) procedure or receiving a TAC MAC CE.

In various embodiments, the disclosed techniques may advantageously allow a network to reallocate PUSCH resources to other UEs when a UE enters an out-of-sync state without causing uplink collisions of the reallocated resources. The network may reactivate the stored SP-CSI configuration of the UE without the network reallocating resources. Embodiments of the present disclosure may be implemented in any of various forms. For example, some embodiments may be implemented as a computer-implemented method, a computer-readable memory medium, or a computer system. Other embodiments may be implemented using one or more custom designed hardware devices, such as ASICs. Other embodiments may be implemented using one or more programmable hardware elements, such as FPGAs.

In some embodiments, the apparatus comprises means for performing one or more of the method elements discussed herein.

In some embodiments, a non-transitory computer-readable memory medium may be configured such that it stores program instructions and/or data, wherein the program instructions, if executed by a computer system, cause the computer system to perform a method, e.g., any of the method embodiments described herein, or any combination of the method embodiments described herein, or any subset of any of the method embodiments described herein, or any combination of such subsets.

In some embodiments, a device (e.g., UE 106) may be configured to include a processor (or a set of processors) and a memory medium, wherein the memory medium stores program instructions, wherein the processor is configured to read and execute the program instructions from the memory medium, wherein the program instructions are executable to implement any of the various method embodiments described herein (or any combination of the method embodiments described herein, or any subset of any of the method embodiments described herein, or any combination of such subsets). The apparatus may be embodied in any of a variety of forms.

Although the above embodiments have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications.

Claims

1. An apparatus, comprising:

one or more processing elements configured to:

starting a Timing Alignment Timer (TAT) in response to a time alignment command from a cellular network for one or more serving cells;

storing a configuration of semi-persistent (SP) Channel State Information (CSI) reports of a Physical Uplink Shared Channel (PUSCH) based on Radio Resource Configuration (RRC) information from the cellular network;

activating configuration of the SP-CSI report based on Downlink Control Information (DCI) from the cellular network;

transmitting one or more SP-CSI reports using the PUSCH according to an active stored configuration; and

deactivating all active stored configurations that use the PUSCH and correspond to SP-CSI reporting of the one or more serving cells in response to expiration of the TAT.

2. The device of claim 1, wherein the device is configured to enter an out-of-sync state in response to expiration of the TAT.

3. The apparatus of claim 2, wherein the deactivation of the stored configuration prevents a conflict between the stored configuration and an SP-CSI report on a PUSCH configured by the cellular network for another UE.

4. The apparatus of claim 2, wherein the apparatus is configured to:

the synchronization state is re-entered based on performing a Random Access Channel (RACH) procedure or receiving a time alignment command medium access control element (TACMAC CE).

5. A non-transitory computer-readable medium having instructions stored thereon that are executable by a computing device to perform operations comprising:

transmitting one or more SP-CSI reports according to the active stored configuration; and

6. The non-transitory computer-readable medium of claim 5, wherein the UE enters an out-of-sync state in response to expiration of the TAT.

7. The non-transitory computer-readable medium of claim 6, wherein the operations further comprise:

8. The non-transitory computer-readable medium of claim 5, wherein the deactivation of the stored configuration avoids a conflict between the stored configuration and uplink communications on a PUSCH configured by the cellular network for another UE.

9. An apparatus, comprising:

one or more processing elements configured to:

tracking an amount of time elapsed since a last time alignment with a cellular network for one or more serving cells;

a configuration to store a semi-persistent report of information associated with a wireless channel between the apparatus and the cellular network, wherein the report uses a shared uplink channel;

transmitting one or more reports using the shared uplink channel according to a stored configuration; and

in response to detecting that a predetermined time interval has elapsed since a most recent time alignment with the cellular network, disabling all active stored configurations that use the shared uplink channel and that correspond to reports of the one or more serving cells.

10. The apparatus of claim 9, wherein the apparatus is configured to track an amount of time using a timing alignment timer.

11. The apparatus of claim 10, wherein the apparatus is configured to start the timing alignment timer in response to a time alignment command from the cellular network.

12. The apparatus of claim 11, wherein the time alignment command is included in a Media Access Control (MAC) Control Element (CE).

13. The apparatus of claim 9, wherein the information is channel state information.

14. The apparatus of claim 9, wherein the shared uplink channel is a Physical Uplink Shared Channel (PUSCH).

15. The apparatus of claim 9, wherein the deactivation of the stored configuration avoids a conflict between the stored configuration and uplink communications on a shared uplink channel allocated by the cellular network for another UE.

16. The apparatus of claim 9, wherein the apparatus is configured to enter an out-of-sync state in response to the elapse of the predetermined time interval.

17. The apparatus of claim 16, wherein the apparatus is configured to re-enter a synchronization state based on performing a Random Access Channel (RACH) procedure.

18. The apparatus of claim 16, wherein the apparatus is configured to re-enter a synchronization state based on receiving a time alignment command media access control element (TAC MAC CE).

19. The apparatus of claim 9, further comprising:

one or more antennas; and

one or more wireless radios configured to communicate with the cellular network via the one or more antennas.

20. The apparatus of claim 9, wherein the apparatus is an integrated circuit.